The invention is in the field of high-temperature cooking and particularly concerns wok cooking apparatus, such as wok ranges and wok support structures that incorporate a refractory insulating material. From another aspect, the invention concerns a wok support structure that includes a refractory insulating material to reduce the amount of heat conducted through the structure.
Wok cooking involves the application of intense heat to a wok, a metal cooking pan with a convex bottom. Typically, the heat is applied from a gas burner. High-volume wok cooking as might occur in a restaurant, for example, may employ a wok range with multiple wok cooking stations. In a wok range, a wok cooking station usually consists of a cylindrical or tubular wok support that rises from a heat source such as a gas burner, through a table bed that is penetrated by all of the wok cooking stations of the range. The table bed provides a surface that supports a flow of water used to clean woks between uses and also to conduct heat away from the wok supports.
Heat conduction by the table bed is an inevitable consequence of the operation of a wok range. Wok cooking is performed at temperatures ranging through 2,100xc2x0 F. in order to encapsulate the flavor of the food being cooked and to bond spices and accents to the food. At each wok cooking station, the heat is chimneyed upwardly through a wok support to a wok. A significant amount of the heat provided by way of a wok support is conducted through the support to the table bed. As a consequence, the table bed of a wok range bears an enormous load of heat while the range is in use. Nor is the load continuous. During a busy day the wok cooking stations of a restaurant wok range are cycled on and off many times. In the typical range, hot spots occur between each wok cooking station and the table bed. The result is acceleration of fatigue and warping of the bed. This reduces the lifetime of a wok range and increases the facilities expense of a wok cooking restaurant. Presently, the problem of heat damage is solved by the application of water directly to the table bed. Dissipation of heat by a constant flow of water over the table bed and against the wok supports extends the lifetime of a wok range by reducing the rates of fatigue and warping.
Water flow in the operation of a wok range, however, raises resource, regulatory and economic issues. Because a wok range is in virtually constant use during the working day of a restaurant, water continuously washes over the table bed, past the wok supports. Because it is also used for cleaning, such water is typically not recycled. Thus, wok cooking can add substantially to the total amount of water consumed in the operation of a restaurant with a high daily volume of business (a xe2x80x9chigh volumexe2x80x9d restaurant).
In a high volume restaurant, a large amount of water is consumed in the making of ice, the operation of sinks and toilets, the preparation of food, the serving of beverages, the washing of dishes and cooking implements, and the maintenance of landscaping; call this a xe2x80x9cbase consumptionxe2x80x9d amount. For example, in one high volume restaurant operated by the assignee of this application the base consumption of water was just under 10,000 gallons per day (gpd). In the same restaurant, when the amount of water consumed by high-volume wok cooking conducted on a range with four cooking stations was added, total water consumption, including the base consumption rate and the rate of consumption by the wok range, rose to 25,000 gallons/day (gpd). The installation of pressure regulators and precision valves at the faucets that feed the wok ranges reduced the total consumption rate to 13,000 gpd. This would appear to be a very satisfactory result. Nevertheless, it is anticipated that further reductions will soon be needed. Since the easy and obvious solutions to reducing water consumption are already in use, novel technical advances will be required to achieve additional reduction.
In the United States, there is a growing trend to limit water use by regulation. A number of local and state jurisdictions are considering the regulation by law of commercial and residential water consumption. Proposed ordinances and legislation would set a limit on use and impose penalties for excess consumption. Shut-off of service is one possible penalty. Such a measure would, of course, spell economic disaster for a restaurant.
Finally, the cost of water is rising inexorably. Therefore, in a high volume restaurant, every measure taken to reduce the use of water limits the operating expense resulting from its cost. This is an especially pressing economic consideration in the balance sheet of a high-volume restaurant serving wok-cooked cuisine.
Presume that a target for the total consumption rate of a high-volume restaurant with a multi-station wok range is between 8,000 gpd and 10,000 gpd. Even with the implementation of available water flow control measures, the four station range configuration described above, at 13,000 gpd, fails to meet the target. Accordingly, there is still a distinct and substantial problem in controlling the amount of water consumed in the operation of such wok ranges. The failure to achieve further reductions in the consumption of water and fuel can directly and adversely affect the profitability and competitive ability of a high volume restaurant offering wok-cooked cuisine.
The problem may also be viewed from another aspect. The heat to be dissipated in a wok range emanates principally from the wok supports at the cooking stations. These elements are constructed to support a wok above the table bed and to transfer heat upwardly from a gas burner to the wok. Typically a wok support is made of a sturdy, durable material that tolerates long exposure to high temperatures without significant degradation in its ability to support a heavy wok containing a dense load of cooking food. In this regard, an exemplary wok support includes one or more cylinders of stainless steel that transfer heat not only upwardly to a wok, but also laterally, through the support structure itself, to the table bed. This not only increases the consumption of water needed to cool the table bed, it also increases the amount of fuel necessary to cook food in the wok. With reduction of the transfer of heat to the table bed, the consumption of both water and fuel would be reduced. Thus, there is a distinct and substantial problem in the highly heat conductive characteristic of a wok support.
The problem of water usage in a wok range with a table bed for supporting a flow of water to conduct heat and the problem of heat conduction through a wok support are solved by the invention which provides a novel structure for a wok support that incorporates a refractory insulating material into the structure of the wok support. According to the invention, a wok support includes a tubular support structure having internal space in its wall. The refractory insulating material is disposed in the internal space. When a wok support thus constructed is received in a range to support a wok over a heat source, the amount of heat transferred laterally through the wall is substantially less than the amount of heat transferred laterally through the wall of a tubular wok support without a refractory insulating material integrated into its structure. Consequently, when disposed at the wok stations of a wok range, a plurality of wok supports constructed with refractive insulating material significantly reduce the volume of water necessary to cool the table bed and the amount of fuel necessary to cook, and produce hydrological and fuel resource savings. Since the invention constrains heat load on the table bed, these savings will not be bought with a shortened range lifetime. As a consequence, enhanced profitability and amplified competitive advantage will be realized by a high volume restaurant utilizing a wok range with wok supports constructed according to the invention.